The present invention relates to a sealing device, for example, for a vertical packaging material tube filled with a beverage for sealing the tube transversely thereof when the tube is to be divided into lengths each corresponding to one container to form pillowlike intermediate containers.
As disclosed, for example, in JP-A-61-93011, such a device already known comprises a lift frame, a pair of pressure arms supported by the lift frame each at a lower portion thereof and pivotally movable about respective parallel horizontal axes, a pair of sealing jaws opposed to each other and fixed to the respective pressure arms each at an upper portion of the arm, drive means for pivotally moving the arms to close the sealing jaws when the lift frame is lowered and to open the sealing jaws when the lift frame is raised, a high-frequency heating coil provided on one of the sealing jaws for induction-heating an aluminum foil layer of a tube present between the sealing jaws as closed, and a flexible feeder line connecting the heating coil to a power source.
With the device described, current is supplied to the heating coil through the feeder line, which is repeatedly bent with the up-and-down movement of the lift frame and the pivotal movement of the pressure arms. Accordingly, the feeder line is relatively short in mechanical life, requires frequent periodic inspection and periodic replacement and therefore has the problem of being cumbersome to maintain.